The resolution of seismic data is critical to seismic data processing and the subsequent interpretation of fine structures. In conventional resolution improvement methods, the seismic data is assumed stationary and th...The resolution of seismic data is critical to seismic data processing and the subsequent interpretation of fine structures. In conventional resolution improvement methods, the seismic data is assumed stationary and the noise level not changes with space, whereas the actual situation does not satisfy this assumption, so that results after resolution improvement processing is not up to the expected effect. To solve these problems, we propose a seismic resolution improvement method based on the secondary time-frequency spectrum. First, we propose the secondary time-frequency spectrum based on S transform (ST) and discuss the reflection coefficient sequence and time-dependent wavelet in the secondary time frequency spectrum. Second, using the secondary time frequency spectrum, we design a two- dimensional filter to extract the amplitude spectrum of the time-dependent wavelet. Then, we discuss the improvement of the resolution operator in noisy environments and propose a novel approach for determining the broad frequency range of the resolution operator in the time- fi'equency-space domain. Finally, we apply the proposed method to synthetic and real data and compare the results of the traditional spectrum-modeling deconvolution and Q compensation method. The results suggest that the proposed method does not need to estimate the Q value and the resolution is not limited by the bandwidth of the source. Thus, the resolution of the seismic data is improved sufficiently based on the signal-to-noise ratio (SNR).展开更多
In this study, to explore the radiation protection effects of Lyophyllum Decastes Sing (LDS), a hot distilled-water extract of LDS was orally administered at a dosage of 250mg/kg every other day for a period of 2 we...In this study, to explore the radiation protection effects of Lyophyllum Decastes Sing (LDS), a hot distilled-water extract of LDS was orally administered at a dosage of 250mg/kg every other day for a period of 2 weeks in irradiated mice. An automatic blood cell counter was used to measure white blood cells (lymphocytes, monocyte, and granulocytes) one day before X-ray irradiation, and 3 hours, 12 hours, 24 hours, 3 days, 7 days, 15 days and 30 days after irradiation. The Dunnett test was used to examine statistical significance of differences. The peripheral blood cell counts in the Lyophyllum-administered non-irradiation group revealed an increase in the numbers of ieukocytes, lymphocytes and monocytes. For 2 Gy whole body radiation, a significant statistical difference was found between the X-ray group and the Lyophyllum plus X-ray group in the numbers of leukocytes, lymphocytes and monocytes. The results suggest that Lyophyllum restrains blood cell-count falling after irradiation, which is probably mediated at least in part by hemopoietic function, and NK and LAK activities seems to play a role in preventing secondary irffections associated with irradiation.展开更多
The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deprot...The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deproteinization with Sevag method and ethanol precipitation. The pure schizophyllan was obtained by gel filtration chromatography with Sephacryl S-500,and its molecular characteristics were examined. The result showed that the molecular weight was 3.8×104 ,and the schizophyllan consisted of glucose with β-(1→6)-glucosidic linkages.展开更多
基金financially supported by the National 973 Project(No.2014CB239006)the National Natural Science Foundation of China(No.41104069 and 41274124)the Fundamental Research Funds for Central Universities(No.R1401005A)
文摘The resolution of seismic data is critical to seismic data processing and the subsequent interpretation of fine structures. In conventional resolution improvement methods, the seismic data is assumed stationary and the noise level not changes with space, whereas the actual situation does not satisfy this assumption, so that results after resolution improvement processing is not up to the expected effect. To solve these problems, we propose a seismic resolution improvement method based on the secondary time-frequency spectrum. First, we propose the secondary time-frequency spectrum based on S transform (ST) and discuss the reflection coefficient sequence and time-dependent wavelet in the secondary time frequency spectrum. Second, using the secondary time frequency spectrum, we design a two- dimensional filter to extract the amplitude spectrum of the time-dependent wavelet. Then, we discuss the improvement of the resolution operator in noisy environments and propose a novel approach for determining the broad frequency range of the resolution operator in the time- fi'equency-space domain. Finally, we apply the proposed method to synthetic and real data and compare the results of the traditional spectrum-modeling deconvolution and Q compensation method. The results suggest that the proposed method does not need to estimate the Q value and the resolution is not limited by the bandwidth of the source. Thus, the resolution of the seismic data is improved sufficiently based on the signal-to-noise ratio (SNR).
文摘In this study, to explore the radiation protection effects of Lyophyllum Decastes Sing (LDS), a hot distilled-water extract of LDS was orally administered at a dosage of 250mg/kg every other day for a period of 2 weeks in irradiated mice. An automatic blood cell counter was used to measure white blood cells (lymphocytes, monocyte, and granulocytes) one day before X-ray irradiation, and 3 hours, 12 hours, 24 hours, 3 days, 7 days, 15 days and 30 days after irradiation. The Dunnett test was used to examine statistical significance of differences. The peripheral blood cell counts in the Lyophyllum-administered non-irradiation group revealed an increase in the numbers of ieukocytes, lymphocytes and monocytes. For 2 Gy whole body radiation, a significant statistical difference was found between the X-ray group and the Lyophyllum plus X-ray group in the numbers of leukocytes, lymphocytes and monocytes. The results suggest that Lyophyllum restrains blood cell-count falling after irradiation, which is probably mediated at least in part by hemopoietic function, and NK and LAK activities seems to play a role in preventing secondary irffections associated with irradiation.
基金National Nature Science Foundation of China (No.31171662)"973"National Key Basic Research and Development Program(No.2012CB518202)+1 种基金Project of Qinghai Development of Science and Technology(No.2011-N-150)Key Project of GLD of PLA
文摘The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deproteinization with Sevag method and ethanol precipitation. The pure schizophyllan was obtained by gel filtration chromatography with Sephacryl S-500,and its molecular characteristics were examined. The result showed that the molecular weight was 3.8×104 ,and the schizophyllan consisted of glucose with β-(1→6)-glucosidic linkages.